Which of the following indicates rapid, shallow breathing during a dive?

Rapid, shallow breathing during a dive is often indicated by the exhalation of large bubbles. When a diver breathes rapidly and superficially, they are likely to expel larger bubbles of air due to the hurried nature of their breathing. This pattern can suggest that the diver is experiencing anxiety, discomfort, or is not regulating their breathing effectively, which can be critical to identify for safety during a dive.

In contrast, inhalation of deep breaths would demonstrate controlled and effective breathing, which is the opposite of rapid, shallow breathing. A steady breathing pattern indicates a relaxed and effective approach to breathing underwater, essential for maintaining buoyancy and minimizing the risk of hypercapnia or hypoxia. A calm demeanor typically reflects a relaxed state, which again contradicts the signs of rapid, shallow breathing. Identifying large bubbles during exhalation can signal the need for immediate attention to the diver's breathing technique and overall state.